This invention is concerned with the production of acetaldehyde and ethanol by reaction of carbon monoxide and hydrogen in the presence of a ruthenium catalyst.
Acetaldehyde is a very valuable commercial chemical with a wide variety of uses particularly as an intermediate for production of commercial chemicals. Ethyl alcohol is also an important valuable commercial chemical useful for a wide variety of purposes including as a chemical intermediate, as a solvent, and perhaps more importantly as a component of gasohol.
The reaction of mixtures of carbon monoxide and hydrogen (e.g., synthesis gas) has long been known and can result in a variety of products depending on reaction conditions and the type of catalyst employed. U.S. Pat. No. 2,623,893 describes the reaction of carbon monoxide and hydrogen in the presence of one or more hydrogenation catalysts such as iron, nickel, cobalt or copper oxide-chromium oxide to provide oxygenated compounds such as aldehydes and ketones which are thereafter hydrogenated to the corresponding alcohols. U.S. Pat. No. 2,653,959 describes a process for separating oxygenated compounds, e.g., alcohol, esters, acids, ketones and aldehydes, from the oil phase of the product obtained from the reaction of carbon monoxide and hydrogen over an iron catalyst. U.S. Pat. No. 3,833,634 describes the reaction of carbon monoxide and hydrogen over rhodium catalyst to produce ethylene glycol, propylene glycol, glycerol, methanol, ethanol, methyl acetate and other products. U.S. Pat. No. 4,136,104 describes the conversion of synthesis gas to acetic acid and related oxygenated products such as ethanol, acetaldehyde and ethyl acetate employing a supported rhodium-ruthenium bimetallic alloy as catalyst. U.S. Pat. No. 4,157,338 describes a process for producing hydrocarbon mixtures useful in forming gasoline boiling range products wherein a mixture of carbon monoxide and hydrogen is contacted with a catalyst composition containing ruthenium, rhodium and/or osmium and a crystalline aluminosilicate zeolite. U.S. Pat. No. 4,246,186 describes the conversion of synthesis gas to two-carbon atom oxygenated hydrocarbons, namely, acetic acid, ethanol and acetaldehyde, employing a rhodium metal catalyst. U.K. Pat. No. 940,666 describes the conversion of synthesis gas to hydrocarbons and straight chain alcohols employing prereduced ruthenium chloride as catalyst. French Pat. No. 2,259,077 discloses producing ethanol from carbon monoxide and hydrogen using rhodium on silica gel as catalyst at 300.degree.-350.degree. C. and 1000-2500 psi pressure. West German Specification No. 2,644,185 describes conversion of carbon monoxide and hydrogen to hydrocarbons employing Ru.sub.3 (CO).sub.12 in tetrahydrofuran as solvent. Use of the same ruthenium carbonyl catalyst on solid supports to produce hydrocarbon products is described in J.A.C.S. 100, 2590 (1978). The conversion of carbon monoxide and hydrogen over ruthenium carbonyl clusters to methanol and methyl formate has been described [ACS/CSJ Chemical Congress Abstracts, INORG. 428 (1979)].